GM2a Gangliosidosis

Disease Information: GM2a Gangliosidosis, a lysosomal storage disorder, is a slowly progressing neuromuscular disease. Affected kittens may seem “clumsy”, but by 14 months of age, a lack of motor coordination and abnormal startle response and tremors are apparent.

Inheritance Information: GM2a is autosomal recessive, meaning that animals with two copies of this allele will be affected. Animals with one copy of the gene will be clinically-normal carriers.

The possible genotypes are:

N/N The cat is normal, and cannot produce affected offspring.

N/gm2a The cat is a carrier, and can pass the allele on to approximately 50% of any offspring. If bred to another N/gm2a carrier, approximately 25% of the offspring will be normal, 50% will be carriers, and 25% will be affected.

gm2a/gm2a The cat is affected. If bred to a normal animal, 100% of the offspring will be carriers. If bred to an N/gm2a carrier, 50% of the offspring will be carriers and 50% will be affected.

Recommendations:

– Carriers may be bred to normal animals (N/gm2a x N/N) without any risk of producing affected offspring. The offspring should be tested before breeding to determine if they are carriers or normal.

– Breeding two carriers (N/gm2a x N/gm2a) is not recommended due to the possibility of 25% of the offspring being affected.